One person’s trash is another person’s treasure

Rubina Raja and Søren M Sindbæk on the archaeology of waste

‘Something is rotten in the state of Denmark’ may be one of Shakespeare’s most famous lines. This exclamation in Hamlet immediately draws our thoughts to smells and decomposing rubbish, even if only of the metaphorical kind. However, the whiff of decay we bring to the forefront here is rather more literal than the one Shakespeare had in mind. It is another kind of rot, namely that produced by kitchen middens. This kind of rot provides fascinating insights into the way that ancient people organised themselves in settlements, what they ate, and the stuff that tells us about the continuation or collapse of their societies – both in prehistoric and historic times. It is, in short, the kind of rot that gets most archaeologists excited, when they find it.

As it happens, Shakespeare’s statement was closer to the mark than he might have imagined: certainly, Copenhagen in the 1600s was a city brimming with rubbish. A statute in 1680 instructed the mayor’s secretary to record how the inhabitants dealt with their waste, which tended simply to pile up in the streets. Shortly after that, a solution to the problem offered itself, when it was decided to fill in the medieval moats encircling the city. This was a disposal plan that even the litterbug Copenhageners were willing to follow.

The outcome was brought to light a few years ago, when excavations for the Copenhagen City Metro cut the backfilled moats, and tons of household waste and rotten rags emerged from the deep. A chapter in the fascinating book Archaeologies of Waste details the deposits, buried in the brief period between 1675 and 1685 – a very short span of time in archaeological terms. The finds provide not only a sobering view of diet, health, and subsistence in the European Age of Absolutism, but a memento of posh and not-so-posh habits of dining, drinking, and smoking, as well as faded fashion fads recorded by more than 1,300 pieces of textile.

Another unexpected resonance with Shakespeare’s line is that Denmark is famous – among archaeologists at least – for being home to the first study of a prehistoric kitchen midden. The so-called Køkkenmøddingkommission (‘the Kitchen Midden Commission’) was constituted in 1848 by the Royal Museum for Nordic Antiquities – the predecessor of the present National Museum of Denmark. This commission produced important publications on prehistoric kitchen middens bordering a channel known as Limfjorden in northern Jutland, as well as on Djursland in eastern Jutland. A generation later, a more interdisciplinary team embarked on a sequel, duly named the Second Kitchen Midden Commission, which examined middens at Ertebølle by Limfjorden between 1893 and 1895. Close to 9,000 archaeological objects were excavated across 314m². Furthermore, more than 20,000 animal bones and over 550 charcoal samples were collected. These results were published in a weighty tome entitled Affaldsdynger fra Stenalderen i Danmark (‘Garbage Heaps from the Stone Age in Denmark’), which became a benchmark for archaeological method.

A rotten business

Human trash has thus been studied for many years. However, over the last few decades, new techniques and methods have been pioneered and integrated into archaeological research. Numerous fieldwork projects have integrated cross-disciplinary studies of trash heaps in connection with studies of settlement continuity, human behaviour, historical events – longue durée developments or sudden convulsions – and have even begun to tackle issues such as the potential footprint of climate change, as seen through rubbish heaps. The world today is faced with the challenges of escalating climate crisis, political and military instability, as well as increasingly large movements of people. Given that more than half of the globe’s population currently lives in cities, these challenges are certainly not less than they would have been in earlier eras. While cities facilitate networks – perhaps most obviously between their inhabitants – they also require many resources. These they cannot generate themselves, and they can be as critical as the food they eat. For these, they rely on non-urban sources. Trash allows us to study the resulting networks and their changes over time.

In 2019, a paper published in PNAS reported on settlement rubbish-heaps associated with the Byzantine city of Elusa, in the Negev Desert in modern Israel. Led by Professor Guy Bar-Oz, who directed a cross disciplinary team, the pioneering fieldwork undertaken at the site has produced new, high-definition archaeological data by combining radiocarbon dating with granular study of trash-heap composition. Examining the food stuffs and ceramics dumped across more than a millennium shows – to a much more nuanced degree than previously possible – how a region such as the Negev was vulnerable to even slight changes in the climate: changes that would not have been immediately apparent to humans. These sometimes subtle shifts could lead to reduced water resources, making it difficult or even impossible to maintain, among other things, irrigation systems. While, on the one hand, ancient societies located in deserts can be said to have been among the most resilient – as they were able to survive in a harsh landscape – they were also, on the other hand, particularly vulnerable. This is because even slight changes in the availability of their most important resource, namely water, could spell disaster. An imbalance could threaten food security and trigger societal decline – potentially bringing down the curtain on societies that had flourished for centuries.

Archaeologists from Copenhagen Museum discovered an abundance of household waste while excavating the city rampart at Vesterport in 2012. Image: Copenhagen City Museum

Another study, published in PLOS ONE in 2022, has shown how food security and sustainability can be illuminated in ancient urban contexts, courtesy of evidence that does not necessarily relate directly to trash heaps. This work, focusing on the ancient desert city of Palmyra in Syria, drew on more than a decade of research tackling the city’s funerary portraiture, its grave monuments, its inscriptions, and its overall development, alongside a study of its hinterland. It demonstrates how modelling big archaeological data grants new insights into the number of people who could have lived in the city, and therefore the sustenance needed to sustain them. Palmyra flourished for three centuries, until it was sacked by the Romans in AD 272. Among the evidence it bequeathed to us is the largest group of funerary portraits in the ancient world amassed from a single place (see CWA 111). Refined dating of these sculptures, an understanding of them within their funerary settings, and modelling their development over time – such as the quantity produced and left for us to study – permit fresh insights into historical events in the city, including the impact of epidemics or political and military unrest. Such problems can be balanced against the fruits of stability and the surge in prosperity during the centuries when Palmyra’s elite dominated much of the caravan trade to the East and beyond. This approach allowed researchers to compare these developments with long-distance trade materials and food production in the hinterland of the city. The results allowed new hypotheses to be developed about the impact of slow climate change on food production in and around Palmyra, prompting an earlier decline in societal resilience than hitherto thought.

The lifespan of urban sites and societies, the development of human resilience over centuries, and the impact that climatic and human factors had on settlement can be studied from many angles. Our options will only be enriched if we allow ourselves to incorporate new methodologies and techniques. Such fresh research brings crucial knowledge about human behaviour to the fore, while also reminding us that one person’s trash can be another person’s treasure. As for Shakespeare’s line, it turns out that when power structures fray and societies come unstuck, sometimes even the rot that he had in mind can be detected amid a community’s refuse.

Rubina Raja is professor of classical archaeology and director of the Centre for Urban Network Evolutions, Aarhus University, Denmark. Together with Søren, she is founding editor of the  Journal of Urban Archaeology. 
Søren M Sindbæk is professor of medieval archaeology at Aarhus University, Denmark, and co-director of the Centre for Urban Network Evolutions.